http://ieeexplore.ieee.org/iel5/5/31047/01444179.pdf

Fundamentals of acoustics

Importance of imaging method over imaging modality in noninvasive determination of left ventricular volumes and ejection fraction: Assessment by two- and three-dimensional echocardiography and magnetic resonance imaging

Therapy methods using pulsed cavitational ultrasound therapy can include the subprocesses of initiation, maintenance, therapy, and feedback of the histotripsy process, which involves the creation and maintenance of ensembles of microbubbles and the use of feedback in order to optimize the process based on observed spatial-temporal bubble cloud dynamics. The methods provide for the subdivision or erosion of tissue, liquification of tissue, and/or the enhanced delivery of therapeutic agents. Various feedback mechanisms allow variation of ultrasound parameters and provide control over the pulsed cavitational process, permitting the process to be tuned for a number of applications. Such applications can include specific tissue erosion, bulk tissue homogenization, and delivery of therapeutic agents across barriers.

Pulsed cavitational ultrasound therapy

https://docs.lib.purdue.edu/cgi/viewcontent.cgi?article=2204&context=cstech

Arbitrary topology shape reconstruction from planar cross sections

Background Reliable, serial, noninvasive quantitative estimation of left ventricular ejection fraction is essential for selecting and timing therapeutic interventions in patients with heart disease. Equilibrium radionuclide angiography is widely used for this purpose but has well-recognized limitations. Advantages of echocardiography over equilibrium radionuclide angiography include assessment of wall motion, valvular pathology, and cardiac hemodynamics, in addition to portability, lack of radiation exposure, and substantially lower cost. However, conventional echocardiographic techniques are limited by geometric assumptions, image positioning errors, and use of subjective visual methods. To overcome these limitations, a three-dimensional echocardiographic method was developed. This study compares ejection fraction by three-dimensional echocardiography, quantitative two-dimensional echocardiography, and subjective two-dimensional echocardiographic visual estimation with that by equilibrium radionuclide an...

Assessment of Cardiac Function by Three-dimensional Echocardiography Compared With Conventional Noninvasive Methods

A volume algorithm is established which uses the data generated by computed tomography (CT) or ultrasound scans. The algorithm is based on a polyhedral reconstruction of an object of interest. Phantom studies indicate that the algorithm calculated volume is accurate within 3 percent. In a controlled clinical experiment on a laboratory animal, the algorithm calculated volume showed a maximum error of about 5 percent. In less controllable applications to human clinical data, volume calculations showed variations ranging up to 16 percent.

An Algorithm for Volume Estimation Based on Polyhedral Approxi mation

An ultrasound beam charcterization device is provided which may be employed during manufacture of diagnostic ultrasound equipment or during use thereof in the field in order to determine the beam profile of the ultrasonic transducer. The device includes a substantially air tight enclosure or box, having therein a thin element characterized by the properties of substantially uniform acoustic scattering and a different back scatter coefficient than the surrounding filler medium. The element is preferably oriented along or parallel to the axis of radiation of the transducer, and is advantageously in the form of a synthetic resin cellular foam material having a relatively high scattering level, which may be embedded in a different foam of lower scattering level. A reticulated cellular foam and salt solution fill the remaining volume of the preferred device, thereby permitting the imaging of transducer beam profiles in a tissue equivalent material.

Ultrasonic beam characterization device

Method and apparatus for measuring an attenuation characteristic in a region of interest using ultrasound wherein two statistically independent set of values are accumulated as a difference between logarithms of pairs of each signal set, and the attenuation characteristic calculated as a central tendency parameter of each set of values.

Precision ultrasound attenuation measurement

The CUPAD system described in the previous paper includes a custom designed hardware interface between a Picker EV-6 Scanner and a Digital Equipment Corporation PDP-15 computer, and a supporting software package. This paper will describe in greater detail the structure and operation of the hardware and the software.

The CUPAD System: Real Time Handling of Randomly Acquired Clinical Ultrasound Data

The information available to the physician from clinical ultrasound examinations is limited. Current research in our laboratory has identified some of the limitations found in presently available clinical imaging systems and has suggested ways of making significant improvements. In this paper the structure of our research system (CUPAD) is presented. Some of the current goals of this research are noted, and research schemes designed to achieve some of these goals outlined. A brief description of our acquisition hardware and processing software is provided and initial CUPAD scans discussed.

Jonathan Ophir

Papers

An Algorithm for Volume Estimation Based on Polyhedral Approxi mation

Ultrasonic beam characterization device

Precision ultrasound attenuation measurement

The CUPAD System: Real Time Handling of Randomly Acquired Clinical Ultrasound Data

Research in Ultrasound Image Generation: A Computerized Ultrasound Processing, Acquisition, and Display (CUPAD) System